From caa6934ac70b1dd7d1d4939961da5b23f305d968 Mon Sep 17 00:00:00 2001 From: Julien CHAUVEAU Date: Fri, 12 Dec 2014 22:05:52 +0100 Subject: clk: rockchip: add CLK_IGNORE_UNUSED flag to fix rk3066/rk3188 USB Host This patch adds CLK_IGNORE_UNUSED flag to hclk_usb_peri, hclk_usbotg0 and hclk_usbotg1 because these clocks must remain enabled to use the USB controllers in host mode. This fixes a regression introduced by commit 78eaf6095cc7 ("clk: rockchip: disable unused clocks"). Signed-off-by: Julien CHAUVEAU Fixes: 78eaf6095cc7 ("clk: rockchip: disable unused clocks") Reviewed-by: Romain Perier Tested-by: Romain Perier Signed-off-by: Heiko Stuebner --- drivers/clk/rockchip/clk-rk3188.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/clk/rockchip/clk-rk3188.c b/drivers/clk/rockchip/clk-rk3188.c index c54078960847..5d33cadc8399 100644 --- a/drivers/clk/rockchip/clk-rk3188.c +++ b/drivers/clk/rockchip/clk-rk3188.c @@ -430,8 +430,8 @@ static struct rockchip_clk_branch common_clk_branches[] __initdata = { GATE(0, "hclk_emem_peri", "hclk_peri", 0, RK2928_CLKGATE_CON(4), 7, GFLAGS), GATE(HCLK_EMAC, "hclk_emac", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 0, GFLAGS), GATE(HCLK_NANDC0, "hclk_nandc0", "hclk_peri", 0, RK2928_CLKGATE_CON(5), 9, GFLAGS), - GATE(0, "hclk_usb_peri", "hclk_peri", 0, RK2928_CLKGATE_CON(4), 5, GFLAGS), - GATE(HCLK_OTG0, "hclk_usbotg0", "hclk_peri", 0, RK2928_CLKGATE_CON(5), 13, GFLAGS), + GATE(0, "hclk_usb_peri", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(4), 5, GFLAGS), + GATE(HCLK_OTG0, "hclk_usbotg0", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(5), 13, GFLAGS), GATE(HCLK_HSADC, "hclk_hsadc", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 5, GFLAGS), GATE(HCLK_PIDF, "hclk_pidfilter", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 6, GFLAGS), GATE(HCLK_SDMMC, "hclk_sdmmc", "hclk_peri", 0, RK2928_CLKGATE_CON(5), 10, GFLAGS), @@ -592,7 +592,8 @@ static struct rockchip_clk_branch rk3066a_clk_branches[] __initdata = { GATE(0, "hclk_cif1", "hclk_cpu", 0, RK2928_CLKGATE_CON(6), 6, GFLAGS), GATE(0, "hclk_hdmi", "hclk_cpu", 0, RK2928_CLKGATE_CON(4), 14, GFLAGS), - GATE(HCLK_OTG1, "hclk_usbotg1", "hclk_peri", 0, RK2928_CLKGATE_CON(5), 14, GFLAGS), + GATE(HCLK_OTG1, "hclk_usbotg1", "hclk_peri", CLK_IGNORE_UNUSED, + RK2928_CLKGATE_CON(5), 14, GFLAGS), GATE(0, "aclk_cif1", "aclk_vio1", 0, RK2928_CLKGATE_CON(6), 7, GFLAGS), @@ -680,7 +681,8 @@ static struct rockchip_clk_branch rk3188_clk_branches[] __initdata = { GATE(0, "hclk_imem0", "hclk_cpu", 0, RK2928_CLKGATE_CON(4), 14, GFLAGS), GATE(0, "hclk_imem1", "hclk_cpu", 0, RK2928_CLKGATE_CON(4), 15, GFLAGS), - GATE(HCLK_OTG1, "hclk_usbotg1", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 3, GFLAGS), + GATE(HCLK_OTG1, "hclk_usbotg1", "hclk_peri", CLK_IGNORE_UNUSED, + RK2928_CLKGATE_CON(7), 3, GFLAGS), GATE(HCLK_HSIC, "hclk_hsic", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 4, GFLAGS), GATE(PCLK_TIMER3, "pclk_timer3", "pclk_cpu", 0, RK2928_CLKGATE_CON(7), 9, GFLAGS), -- cgit v1.2.3 From 5039d16abe250102c021557184950c47566170a4 Mon Sep 17 00:00:00 2001 From: Romain Perier Date: Fri, 12 Dec 2014 17:50:39 +0000 Subject: clk: rockchip: Fix clock gate for rk3188 hclk_emem_peri Do not disable clock gate "hclk_emem_peri", otherwise EMAC clocks no longer work and it breaks ethernet on RK3066 and RK3188. It fixes a regression introduced by commit 78eaf6095cc7 ("clk: rockchip: disable unused clocks"). Signed-off-by: Romain Perier Fixes: 78eaf6095cc7 ("clk: rockchip: disable unused clocks") Signed-off-by: Heiko Stuebner --- drivers/clk/rockchip/clk-rk3188.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clk/rockchip/clk-rk3188.c b/drivers/clk/rockchip/clk-rk3188.c index 5d33cadc8399..b32fcdaea699 100644 --- a/drivers/clk/rockchip/clk-rk3188.c +++ b/drivers/clk/rockchip/clk-rk3188.c @@ -427,7 +427,7 @@ static struct rockchip_clk_branch common_clk_branches[] __initdata = { /* hclk_peri gates */ GATE(0, "hclk_peri_axi_matrix", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(4), 0, GFLAGS), GATE(0, "hclk_peri_ahb_arbi", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(4), 6, GFLAGS), - GATE(0, "hclk_emem_peri", "hclk_peri", 0, RK2928_CLKGATE_CON(4), 7, GFLAGS), + GATE(0, "hclk_emem_peri", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(4), 7, GFLAGS), GATE(HCLK_EMAC, "hclk_emac", "hclk_peri", 0, RK2928_CLKGATE_CON(7), 0, GFLAGS), GATE(HCLK_NANDC0, "hclk_nandc0", "hclk_peri", 0, RK2928_CLKGATE_CON(5), 9, GFLAGS), GATE(0, "hclk_usb_peri", "hclk_peri", CLK_IGNORE_UNUSED, RK2928_CLKGATE_CON(4), 5, GFLAGS), -- cgit v1.2.3 From 12551f0239b50c88352e3292dd7703382addbf5e Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Wed, 24 Dec 2014 14:31:06 +0100 Subject: clk: rockchip: fix rk3066 pll lock bit location The bit locations indicating the locking status of the plls on rk3066 are shifted by one to the right when compared to the rk3188, bits [7:4] instead of [8:5] on the rk3188, thus indicating the locking state of the wrong pll or a completely different information in case of the gpll. The recently introduced pll init code exposed that problem on some rk3066 boards when it tried to bring the boot-pll value in line with the value from the rate table. Fix this by defining separate pll definitions for rk3066 with the correct locking indices. Signed-off-by: Heiko Stuebner Fixes: 2c14736c75db ("clk: rockchip: add clock driver for rk3188 and rk3066 clocks") Tested-by: FUKAUMI Naoki Cc: stable@vger.kernel.org --- drivers/clk/rockchip/clk-rk3188.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/clk/rockchip/clk-rk3188.c b/drivers/clk/rockchip/clk-rk3188.c index b32fcdaea699..7eb684c50d42 100644 --- a/drivers/clk/rockchip/clk-rk3188.c +++ b/drivers/clk/rockchip/clk-rk3188.c @@ -210,6 +210,17 @@ PNAME(mux_sclk_hsadc_p) = { "hsadc_src", "hsadc_frac", "ext_hsadc" }; PNAME(mux_mac_p) = { "gpll", "dpll" }; PNAME(mux_sclk_macref_p) = { "mac_src", "ext_rmii" }; +static struct rockchip_pll_clock rk3066_pll_clks[] __initdata = { + [apll] = PLL(pll_rk3066, PLL_APLL, "apll", mux_pll_p, 0, RK2928_PLL_CON(0), + RK2928_MODE_CON, 0, 5, 0, rk3188_pll_rates), + [dpll] = PLL(pll_rk3066, PLL_DPLL, "dpll", mux_pll_p, 0, RK2928_PLL_CON(4), + RK2928_MODE_CON, 4, 4, 0, NULL), + [cpll] = PLL(pll_rk3066, PLL_CPLL, "cpll", mux_pll_p, 0, RK2928_PLL_CON(8), + RK2928_MODE_CON, 8, 6, ROCKCHIP_PLL_SYNC_RATE, rk3188_pll_rates), + [gpll] = PLL(pll_rk3066, PLL_GPLL, "gpll", mux_pll_p, 0, RK2928_PLL_CON(12), + RK2928_MODE_CON, 12, 7, ROCKCHIP_PLL_SYNC_RATE, rk3188_pll_rates), +}; + static struct rockchip_pll_clock rk3188_pll_clks[] __initdata = { [apll] = PLL(pll_rk3066, PLL_APLL, "apll", mux_pll_p, 0, RK2928_PLL_CON(0), RK2928_MODE_CON, 0, 6, 0, rk3188_pll_rates), @@ -737,8 +748,8 @@ static void __init rk3188_common_clk_init(struct device_node *np) static void __init rk3066a_clk_init(struct device_node *np) { rk3188_common_clk_init(np); - rockchip_clk_register_plls(rk3188_pll_clks, - ARRAY_SIZE(rk3188_pll_clks), + rockchip_clk_register_plls(rk3066_pll_clks, + ARRAY_SIZE(rk3066_pll_clks), RK3066_GRF_SOC_STATUS); rockchip_clk_register_branches(rk3066a_clk_branches, ARRAY_SIZE(rk3066a_clk_branches)); -- cgit v1.2.3 From 9880d4277f6aab6b21404c824f9d9c652ba518ac Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Thu, 18 Dec 2014 20:06:57 +0100 Subject: clk: rockchip: fix rk3288 cpuclk core dividers Commit 0e5bdb3f9fa5 (clk: rockchip: switch to using the new cpuclk type for armclk) didn't take into account that the divider used on rk3288 are of the (n+1) type. The rk3066 and rk3188 socs use more complex divider types making it necessary for the list-elements to be the real register-values to write. Therefore reduce divider values in the table accordingly so that they really are the values that should be written to the registers and match the dividers actually specified for the rk3288. Reported-by: Sonny Rao Fixes: 0e5bdb3f9fa5 ("clk: rockchip: switch to using the new cpuclk type for armclk") Signed-off-by: Heiko Stuebner Reviewed-by: Doug Anderson Cc: stable@vger.kernel.org --- drivers/clk/rockchip/clk-rk3288.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) (limited to 'drivers') diff --git a/drivers/clk/rockchip/clk-rk3288.c b/drivers/clk/rockchip/clk-rk3288.c index ac6be7c0132d..11194b8329fe 100644 --- a/drivers/clk/rockchip/clk-rk3288.c +++ b/drivers/clk/rockchip/clk-rk3288.c @@ -145,20 +145,20 @@ struct rockchip_pll_rate_table rk3288_pll_rates[] = { } static struct rockchip_cpuclk_rate_table rk3288_cpuclk_rates[] __initdata = { - RK3288_CPUCLK_RATE(1800000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1704000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1608000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1512000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1416000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1200000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE(1008000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 816000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 696000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 600000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 408000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 312000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 216000000, 2, 4, 2, 4, 4), - RK3288_CPUCLK_RATE( 126000000, 2, 4, 2, 4, 4), + RK3288_CPUCLK_RATE(1800000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1704000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1608000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1512000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1416000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1200000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE(1008000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 816000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 696000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 600000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 408000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 312000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 216000000, 1, 3, 1, 3, 3), + RK3288_CPUCLK_RATE( 126000000, 1, 3, 1, 3, 3), }; static const struct rockchip_cpuclk_reg_data rk3288_cpuclk_data = { -- cgit v1.2.3 From dca1a4b5ff6e2c25adeff366eb06270dadeab3db Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Tue, 13 Jan 2015 15:44:06 +0100 Subject: clk: at91: keep slow clk enabled to prevent system hang All slow clk users are not properly claiming it (get + prepare + enable) before using it. If all users properly claiming this clock release it, the clock is disabled, but faulty users still depends on it, and the system hangs. This fix prevents the slow clock from being disabled, and should solve the hanging issue, but offending drivers should be patched to properly claim this clock. Signed-off-by: Boris Brezillon Reported-by: Bo Shen Cc: stable@vger.kernel.org Signed-off-by: Michael Turquette --- drivers/clk/at91/clk-slow.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'drivers') diff --git a/drivers/clk/at91/clk-slow.c b/drivers/clk/at91/clk-slow.c index 32f7c1b36204..2f13bd5246b5 100644 --- a/drivers/clk/at91/clk-slow.c +++ b/drivers/clk/at91/clk-slow.c @@ -70,6 +70,7 @@ struct clk_sam9x5_slow { #define to_clk_sam9x5_slow(hw) container_of(hw, struct clk_sam9x5_slow, hw) +static struct clk *slow_clk; static int clk_slow_osc_prepare(struct clk_hw *hw) { @@ -357,6 +358,8 @@ at91_clk_register_sam9x5_slow(void __iomem *sckcr, clk = clk_register(NULL, &slowck->hw); if (IS_ERR(clk)) kfree(slowck); + else + slow_clk = clk; return clk; } @@ -433,6 +436,8 @@ at91_clk_register_sam9260_slow(struct at91_pmc *pmc, clk = clk_register(NULL, &slowck->hw); if (IS_ERR(clk)) kfree(slowck); + else + slow_clk = clk; return clk; } @@ -465,3 +470,25 @@ void __init of_at91sam9260_clk_slow_setup(struct device_node *np, of_clk_add_provider(np, of_clk_src_simple_get, clk); } + +/* + * FIXME: All slow clk users are not properly claiming it (get + prepare + + * enable) before using it. + * If all users properly claiming this clock decide that they don't need it + * anymore (or are removed), it is disabled while faulty users are still + * requiring it, and the system hangs. + * Prevent this clock from being disabled until all users are properly + * requesting it. + * Once this is done we should remove this function and the slow_clk variable. + */ +static int __init of_at91_clk_slow_retain(void) +{ + if (!slow_clk) + return 0; + + __clk_get(slow_clk); + clk_prepare_enable(slow_clk); + + return 0; +} +arch_initcall(of_at91_clk_slow_retain); -- cgit v1.2.3 From b71e8ecd57c8aae5b1815782c47b74ffe3efc09a Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Wed, 31 Dec 2014 16:57:52 +0800 Subject: clk: berlin: bg2q: remove non-exist "smemc" gate clock The "smemc" clock is removed on BG2Q SoCs. In fact, bit19 of clkenable register is for nfc. Current code use bit19 for non-exist "smemc" incorrectly, this prevents eMMC from working due to the sdhci's "core" clk is still gated. Signed-off-by: Jisheng Zhang Cc: stable@vger.kernel.org # 3.16+ Signed-off-by: Michael Turquette --- drivers/clk/berlin/bg2q.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clk/berlin/bg2q.c b/drivers/clk/berlin/bg2q.c index 21784e4eb3f0..440ef81ab15c 100644 --- a/drivers/clk/berlin/bg2q.c +++ b/drivers/clk/berlin/bg2q.c @@ -285,7 +285,6 @@ static const struct berlin2_gate_data bg2q_gates[] __initconst = { { "pbridge", "perif", 15, CLK_IGNORE_UNUSED }, { "sdio", "perif", 16, CLK_IGNORE_UNUSED }, { "nfc", "perif", 18 }, - { "smemc", "perif", 19 }, { "pcie", "perif", 22 }, }; -- cgit v1.2.3 From a5e1baf7dca10f8cf945394034013260297bc416 Mon Sep 17 00:00:00 2001 From: Heiko Stübner Date: Fri, 16 Jan 2015 17:52:44 +0100 Subject: clk: rockchip: fix deadlock possibility in cpuclk Lockdep reported a possible deadlock between the cpuclk lock and for example the i2c driver. CPU0 CPU1 ---- ---- lock(clk_lock); local_irq_disable(); lock(&(&i2c->lock)->rlock); lock(clk_lock); lock(&(&i2c->lock)->rlock); *** DEADLOCK *** The generic clock-types of the core ccf already use spin_lock_irqsave when touching clock registers, so do the same for the cpuclk. Signed-off-by: Heiko Stuebner Reviewed-by: Doug Anderson Signed-off-by: Michael Turquette [mturquette@linaro.org: removed initialization of "flags"] --- drivers/clk/rockchip/clk-cpu.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/clk/rockchip/clk-cpu.c b/drivers/clk/rockchip/clk-cpu.c index 75c8c45ef728..8539c4fd34cc 100644 --- a/drivers/clk/rockchip/clk-cpu.c +++ b/drivers/clk/rockchip/clk-cpu.c @@ -124,10 +124,11 @@ static int rockchip_cpuclk_pre_rate_change(struct rockchip_cpuclk *cpuclk, { const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data; unsigned long alt_prate, alt_div; + unsigned long flags; alt_prate = clk_get_rate(cpuclk->alt_parent); - spin_lock(cpuclk->lock); + spin_lock_irqsave(cpuclk->lock, flags); /* * If the old parent clock speed is less than the clock speed @@ -164,7 +165,7 @@ static int rockchip_cpuclk_pre_rate_change(struct rockchip_cpuclk *cpuclk, cpuclk->reg_base + reg_data->core_reg); } - spin_unlock(cpuclk->lock); + spin_unlock_irqrestore(cpuclk->lock, flags); return 0; } @@ -173,6 +174,7 @@ static int rockchip_cpuclk_post_rate_change(struct rockchip_cpuclk *cpuclk, { const struct rockchip_cpuclk_reg_data *reg_data = cpuclk->reg_data; const struct rockchip_cpuclk_rate_table *rate; + unsigned long flags; rate = rockchip_get_cpuclk_settings(cpuclk, ndata->new_rate); if (!rate) { @@ -181,7 +183,7 @@ static int rockchip_cpuclk_post_rate_change(struct rockchip_cpuclk *cpuclk, return -EINVAL; } - spin_lock(cpuclk->lock); + spin_lock_irqsave(cpuclk->lock, flags); if (ndata->old_rate < ndata->new_rate) rockchip_cpuclk_set_dividers(cpuclk, rate); @@ -201,7 +203,7 @@ static int rockchip_cpuclk_post_rate_change(struct rockchip_cpuclk *cpuclk, if (ndata->old_rate > ndata->new_rate) rockchip_cpuclk_set_dividers(cpuclk, rate); - spin_unlock(cpuclk->lock); + spin_unlock_irqrestore(cpuclk->lock, flags); return 0; } -- cgit v1.2.3 From 176a107b868781c8d6868454aea7d07e0b82d6b8 Mon Sep 17 00:00:00 2001 From: Kevin Hao Date: Wed, 3 Dec 2014 16:53:51 +0800 Subject: Revert "clk: ppc-corenet: Fix Section mismatch warning" This reverts commit da788acb28386aa896224e784954bb73c99ff26c. That commit tried to fix the section mismatch warning by moving the ppc_corenet_clk_driver struct to init section. This is definitely wrong because the kernel would free the memories occupied by this struct after boot while this driver is still registered in the driver core. The kernel would panic when accessing this driver struct. Cc: stable@vger.kernel.org # 3.17 Signed-off-by: Kevin Hao Acked-by: Scott Wood Signed-off-by: Michael Turquette --- drivers/clk/clk-ppc-corenet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clk/clk-ppc-corenet.c b/drivers/clk/clk-ppc-corenet.c index b6e6c85507a5..0a47d6f49cd6 100644 --- a/drivers/clk/clk-ppc-corenet.c +++ b/drivers/clk/clk-ppc-corenet.c @@ -291,7 +291,7 @@ static const struct of_device_id ppc_clk_ids[] __initconst = { {} }; -static struct platform_driver ppc_corenet_clk_driver __initdata = { +static struct platform_driver ppc_corenet_clk_driver = { .driver = { .name = "ppc_corenet_clock", .of_match_table = ppc_clk_ids, -- cgit v1.2.3 From c7662fc59ca38517e0ec04ceaa123ed8209ab6bf Mon Sep 17 00:00:00 2001 From: Stanimir Varbanov Date: Mon, 5 Jan 2015 18:04:23 +0200 Subject: clk: fix possible null pointer dereference The commit 646cafc6 (clk: Change clk_ops->determine_rate to return a clk_hw as the best parent) opens a possibility for null pointer dereference, fix this. Signed-off-by: Stanimir Varbanov Reviewed-by: Stephen Boyd Signed-off-by: Michael Turquette --- drivers/clk/clk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index f4963b7d4e17..d48ac71c6c8b 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -1366,7 +1366,7 @@ static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate) new_rate = clk->ops->determine_rate(clk->hw, rate, &best_parent_rate, &parent_hw); - parent = parent_hw->clk; + parent = parent_hw ? parent_hw->clk : NULL; } else if (clk->ops->round_rate) { new_rate = clk->ops->round_rate(clk->hw, rate, &best_parent_rate); -- cgit v1.2.3